Android-高级UI控件_Menu菜单

代码

Activity01

package com.lxt008;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;

public class Activity01 extends Activity
{
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }

    /*创建menu*/
    public boolean onCreateOptionsMenu(Menu menu)
    {
        MenuInflater inflater = getMenuInflater();
        //设置menu界面为res/menu/menu.xml
        inflater.inflate(R.menu.menu, menu);
        return true;
    }

    /*处理菜单事件*/
    public boolean onOptionsItemSelected(MenuItem item)
    {
        //得到当前选中的MenuItem的ID,
        int item_id = item.getItemId();

        switch (item_id)
        {
            case R.id.about:
                /* 新建一个Intent对象 */
                Intent intent = new Intent();
                /* 指定intent要启动的类 */
                intent.setClass(Activity01.this, Activity02.class);
                /* 启动一个新的Activity */
                startActivity(intent);
                /* 关闭当前的Activity */
                Activity01.this.finish();
                break;
            case R.id.exit:
                Activity01.this.finish();
                break;
        }
        return true;
    }
}

Activity02

package com.lxt008;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

public class Activity02 extends Activity
{
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        /* 设置显示main2.xml布局 */
        setContentView(R.layout.main2);
    }

    /*创建menu*/
    public boolean onCreateOptionsMenu(Menu menu)
    {
        //为menu添加内容
        menu.add(0, 0, 0, R.string.ok);
        menu.add(0, 1, 1, R.string.back);
        return true;
    }

    /*处理menu的事件*/
    public boolean onOptionsItemSelected(MenuItem item)
    {
        //得到当前选中的MenuItem的ID,
        int item_id = item.getItemId();

        switch (item_id)
        {
            case 0:
            case 1:
                /* 新建一个Intent对象 */
                Intent intent = new Intent();
                /* 指定intent要启动的类 */
                intent.setClass(Activity02.this, Activity01.class);
                /* 启动一个新的Activity */
                startActivity(intent);
                /* 关闭当前的Activity */
                Activity02.this.finish();
                break;
        }
        return true;
    }
}

布局

menu

<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:id="@+id/about"
          android:title="关于" />
    <item android:id="@+id/exit"
          android:title="退出" />
</menu>

main

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/hello"
    />
</LinearLayout>

main2

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/hello2"
    >
    </TextView>
</LinearLayout>

string

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">主界面,点击关于会跳到另一个界面!（Activity01）</string>
    <string name="hello2">关于\nAndroid Menu使用范例！（Activity02）</string>
    <string name="app_name">lxt008 Android Demo</string>
    <string name="ok">确定</string>
    <string name="back">返回</string>
</resources>